Last updateMon, 19 Mar 2018 6pm


Custom Valve Training: Lessons Learned at the LACSD

Custom Valve Training: Lessons Learned at the LACSD

Fifty engineers from the Los Angeles Cou...

Intelligent Servicing of Valves During Aging Plant Shutdowns

Intelligent Servicing of Valves During Aging Plant Shutdowns

Shutdowns, turnarounds and outages (STOs...

When Valves Get Wet

When Valves Get Wet

Hurricane Harvey stalled over Houston in...

Valve Stem Material Selection for Offshore Actuated Valves

Valve Stem Material Selection for Offshore Actuated Valves

This article aims to resolve the problem...



• Print magazine
Digital magazine
• VALVE eNews
Read the latest issue

*to qualified valve professionals in the U.S./Canada

The Weekly Report

New Products

  • ja-news-2
  • ja-news-3

Industry Headlines

Could the U.S. Get Carbon Capture Back on Track?

Monday, 19 March 2018  |  Chris Guy

The 2018 U.S. Budget Bill, passed by the House and Senate in mid-February, will shape funding for energy technologies for the next decade. Alongside t...



Industry Headlines

Emerson Supplying Software to Pin Oak Terminals


Pin Oak Terminals, a new hydrocarbon liquids storage and logistics terminal in Mount Airy, LA, has selected Emerson to provide its Synthesis order-to-cash software. Emerson will provide a configured software solution that includes interfaces for operational information, order management, inventory man...


DeZURIK Expanding, Opening New Facility


DeZURIK, Inc. plans to expand production at its Sartell, MN headquarters and open a new rapid fulfillment facility near Houston. The target date for completion of the transition is March of 2019.

Production will gradually be phased out of the company’s existing Schaumburg, IL location. Roughly tw...


Could the U.S. Get Carbon Capture Back on Track?


The 2018 U.S. Budget Bill, passed by the House and Senate in mid-February, will shape funding for energy technologies for the next decade. Alongside the extension of renewable tax credits and credits for energy efficiency, nuclear and fuel cells, the bill contains a provision that could provide the ...


Daelim, PTTGC to Build Ohio Petrochemical Plant


South Korean-based Daelim, through its U.S. subsidiary, is joining with PTTGC America on a feasibility study for a petrochemical ethane cracker complex in Belmont County, OH. Although a final investment decision on the project has not yet been made, PTTGC already has invested more than $100 million ...


U.S. Industrial Production Rose 1.1% in February


Industrial production rose 1.1% in February following a decline of 0.3% in January. Manufacturing production increased 1.2% in February, its largest gain since October. Mining output jumped 4.3%, mostly reflecting strong gains in oil and gas extraction.

In February, manufacturing output increased 1.2%....


Survey Shows Inflation Expectations Moving Higher


The Federal Reserve Bank of New York released the February 2018 Survey of Consumer Expectations, which shows a slight increase in short- and medium- term inflation expectations. Consumers' expectations about their personal financial situations continued to improve . Expectations about changes in taxes...



A Case for Mechanical Temperature Control

vmwnt12_beyond_valves_fig1Instrument, mechanical or project engineers may see a multitude of temperature applications cross their desks. Their immediate reaction might be to employ a temperature control loop. But could a mechanical, self-operated temperature regulator be a better solution for the valve application?

When approaching a temperature control application, the engineer usually considers:

  • The degree of accuracy needed
  • Whether the application requires feedback (Are limit switches/output signals used?)
  • Whether the application needs to be controlled through a DCS, PLC or other type of controller
  • The budget for the application.

The answer to whether a mechanical temperature regulator might be a cost-effective and reliable solution for the application depends on those considerations.

In almost any process facility, a variety of temperature control applications can be found. As with any controlled variable, both the accuracy and criticality of those applications can vary widely. Often, non-critical temperature applications become instrumented control loops even when a self-operated or mechanical regulator could provide the desired accuracy along with a substantial cost savings.


vmwnt12_beyond_valves_fig1Figure 1. Temperature regulatorA typical temperature control loop ­(Figure 1) requires:

  • a temperature sensor
  • wiring and conduit
  • connection to a controlling device
  • a control valve (and sometimes a positioner and/or I/P converter, and an air-filter regulator)
  • plant air

A self-contained temperature regulator requires no power, no air supply or other expensive compo­nents to operate. Representative costs based on a 1-inch line size would be:

  • Temperature transmitter: $300-1,000
  • Temperature controller: $400-1,000
  • Control valve and actuator: $1,500-3,000
  • I/P converter: $200-350
  • Air set regulator: $100-150
  • Positioner: $500-2,000
  • Control loop total: $3,000-7,500
  • Temperature regulator: $500-2,500

Although designs may vary from manufacturer to manufacturer, most temperature regulators operate on the same principle. A premeasured amount of “fill” is drawn into the thermal system filling the upper diaphragm chamber, the capillary tube and most of the bulb. As the controlled temperature increases, the fill in the sensing bulb begins to vaporize and creates pressure on the sealed system. This pressure drives the valve stem, closing direct-acting valves or opening reverse-acting valves. By using different fill fluids, many different temperature control ranges can be offered for both cooling and heating applications—temperature ranges are readily available from -20° F (-29° C) to 500° F (260° C).

Applications for which these devices might be ideal include tank farms, large heat exchangers, heat exchangers with slow temperature changes, area heating/cooling (warehouse/maintenance shops) and steam tracing.

  • Latest Post

  • Popular

  • Links

  • Events


Looking for a career in the Valve Industry?

ValveCareers Horiz

To learn more, watch the videos below or visit ValveCareers.com a special initiative of the Valve Manufacturers Association